Mutant pso8-1 of Saccharomyces cerevisiae, sensitive to photoactivated psoralens, UV radiation, and chemical mutagens, contains a rad6 missense mutant allele.

A novel mutant isolate of Saccharomyces cerevisiae, sensitive to photoactivated mono- and bi-functional psoralens, to UV at 254 nm (UVC), and to nitrosoguanidine, was found to complement the photoactivated psoralen-sensitivity phenotype conferred by the pso1- pso7 mutations and was therefore named pso8-1. A constructed pso8-1 rad4-4 double mutant was super-sensitive ...
to UVC, thus indicating a synergistic interaction of the two mutant alleles. Molecular cloning via complementation of the pso8 mutant's sensitivity phenotype and genetic studies revealed that pso8 is allelic to RAD6. While a pso8-1 mutant had low mutagen-induced mutability, homoallelic diploids showed nearly wild-type sporulation. Sequence analysis of the mutant allele showed pso8-1 to contain a novel, hitherto undescribed T-->C transition in nucleotide position 191, leading to a substitution by leucine of a highly conserved proline at position 64, Rad6-[P64L], which may have severe consequences for the tertiary structure (and hence binding to Rad18p) of the mutant protein.
Mesh Terms:
Alleles, Amino Acid Sequence, Conserved Sequence, Genes, Fungal, Methylnitronitrosoguanidine, Molecular Sequence Data, Mutagens, Mutation, Missense, Phenotype, Photochemistry, Photosensitizing Agents, Phylogeny, Psoralens, Saccharomyces cerevisiae, Saccharomyces cerevisiae Proteins, Sequence Homology, Amino Acid, Ultraviolet Rays
Curr. Genet.
Date: Jul. 01, 2002
Download Curated Data For This Publication
17297
Switch View:
  • Interactions 1